KR100244613B1 - Absorbent article with bolstering waist feature - Google Patents

Abstract

An absorbent product is provided having a supportive waist portion. In a preferred embodiment, the supportive waist portion expands when the supportive waist portion that effectively tightens the diaper by stretching the waist region of the absorbent article is exposed to aqueous body fluid. The result is an increase in retraction in the lateral tension bands in the waist region of the absorbent product, thus reducing the risk of back leakage. The supportive waist portion provides a member that prevents longitudinal bending in the waist region of the absorbent article, particularly in the waist region adjacent the wearer's abdomen. This member also acts as a " support " that resists forces such as gravity, which tends to cause the absorbent product to slide down. The absorbent article is preferably further provided with an absorbent core comprising one or more redistribution components capable of redistributing the aqueous body fluid from the crotch region to the waist region of the absorbent article. The redistribution component is in effective fluid communication with the supportive waist portion.

Description

ABSORBENT ARTICLE WITH BOLSTERING WAIST FEATURE}

Infants and other people with urinary incontinence wear absorbent products, such as diapers, which receive and contain urine and other body emissions. The absorbent product contains the released substance and has two functions to isolate it from the wearer's body and the wearer's underwear and bedding. Many disposable absorbent articles with different basic designs are known in the art. For example, US Pat. No. 26,152, issued to Jan. 31, 1967 to Duncan and Baker, discloses a disposable diaper that is widely used and sold successfully. U.S. Patent No. 3,860,003, issued to Buell on January 14, 1975, discloses a widely used, successfully sold, elasticized leg cuff disposable diaper.

However, absorbent products of the current technology tend to sag or break from the wearer's body during wear and slide / peel along the wearer's body. The following three failure modalities are found to be the reason for the sag, flaking, slipping and peeling:

1) The force exerted by the wearer's general movement each time the wearer breathes, moves, and changes posture can displace the diaper waist region during normal use, thereby reducing the gasket effect at the waist.

2) Due to the general movement of the wearer, the lateral tension band generated by the fixation system of the absorbent product may fall from the wearer's abdomen down to the wearer's abdomen. This is because the irregularly shaped volume causes the tension band to cross into the cross section with the minimum peripheral length for that volume. Typically, the absorbent article is secured around the wearer's waist or near the wearer's navel, while the minimum peripheral length around the wearer crosses the back waist point slightly past the abdomen in the wearer's abdomen. As a result, the tension bands tend to move towards the line of minimum peripheral length. The downward force that occurs when the body discharge is loaded into the absorbent product also causes this slip / peel off.

3) deformation of the absorbent product itself. For example, the elastic element of the diaper has a property known as stress relaxation, which is an inherent property of the polymerization system such as that used as an elastic member in the elastic element of diaper technology to provide a tension band around the wearer's waist. That is, the contracting force exerted by the elastic member decreases with time, thereby reducing the force exerted by the tension band around the wearer's waist and causing the above-mentioned sagging, flaking or peeling. Also, for a discussion of stress relaxation, see Billmeyer Jr., F.W., Textbook of Polymer Science, John Wiley & Sons, pp 188-190, can be found in many textbooks on polymer science.

The sagging, flaking, slipping and peeling can result in the final result of premature leakage and loss of fixation of the absorbent product around the wearer, especially in the waist region of the absorbent product.

In order to deal with premature leakage in the treatment area of absorbent articles, certain commercially available absorbent articles have been provided with elasticized waist portions. This elasticized waist allows the absorbent article to be more comfortably secured around the wearer's waist. An example of a disposable diaper having an elasticized waist portion that has been widely used and sold is described in US Pat. No. 4,515,595, issued to Kievit et al. On May 7, 1985. The elasticized waist portion typically includes an elasticized waist band that is resiliently attached between the topsheet and the backsheet at the ends of the absorbent article. Thus, the elasticized waistband is designed to expand and contract in response to the wearer's movement and to maintain the fixation of the absorbent article around the wearer's waist during use (ie, provide supported dynamic fixation).

However, absorbent articles having the elasticized waist portion designed to be secured at or near the navel also tend to sag, flare, slip or peel off during use. In addition, the elasticized waist portion tends to be displaced in front of the diaper, resulting in poor fixation around the waist of the wearer. For male wearers, in particular, dislocations increase the risk of back leakage because male urination flow is often directed to the waist due to the male body.

Thus, it would be advantageous to provide an absorbent article having a waist portion that provides improved fixation, reduced leakiness, and enhanced wearer stability. It is also advantageous to provide an absorbent article in which sagging, flaring and dislocation at the diaper waist during use is reduced and the overall slip / peel of the absorbent article or absorbent core is reduced.

It is therefore an object of the present invention to provide an absorbent article having dynamic fixation supported around the wearer's waist during use.

It is also an object of the present invention to provide an absorbent article having a unique supportive waist portion that provides support for dynamic fixation and improved leak resistance during use.

It is also an object of the present invention to provide an absorbent article having a unique supportive waist portion that reduces sagging, spreading or dislocation of the diaper front during use, and overall slip / peel off of the absorbent article or absorbent core.

Yet another object is to provide an absorbent article having a unique supportive waist portion that compensates for the loss of fixation due to stress relaxation of the elastic component providing tension around the wearer waist region.

The above and other objects of the present invention will become more apparent when the following detailed description is considered and the accompanying drawings are considered.

Summary of the Invention

The present invention provides an absorbent product, such as disposable diapers, urine incontinence patient briefs, training pants, and the like having a unique supportive waist portion that improves the dynamic fixability of the absorbent product and reduces the risk of premature waist leakage.

Preferred absorbent articles of the invention preferably comprise a liquid permeable topsheet, a liquid impermeable backsheet, an absorbent core located between the topsheet and the backsheet, between the first transverse end of the absorbent core and the first transverse end of the absorbent article. And a retaining combination comprising a supportive waist portion longitudinally positioned at and a securing system for generating / maintaining lateral tension through at least a portion of the peripheral length of the absorbent article. In the most preferred embodiment, the supportive waist portion is integral with the absorbent core and the absorbent article of the present invention is further provided with side flap pairs extending laterally from the longitudinal edge of the retaining combination in both waist regions. Preferably the side flaps provided in the second waist region are elasticized.

The supportive waist portion provides a member that prevents longitudinal bending in the waist region of the absorbent article of the present invention. By not bending, the supportive lumbar portion reduces the risk of lumbar leakage, especially due to curling and sagging / opening in the lumbar region.

In addition, the supportive waist portion cooperates with the core to prevent fixation loss caused by lowering the waist of the absorbent product. The supportive waist portion and the absorbent core cooperate to form a " base " that resists forces such as body movement and loading of body discharges that lower the waist of the absorbent product.

The supportive waist portion also compensates for the stress relaxation of the polymer component, in particular the loss of retraction force over time of the tension bands present in the waist region of the absorbent article due to the stress relaxation of the elastic members that provide the tension. The loss of retraction may cause the absorbent product to slide with an increased risk of premature leakage. The supportive waist portion of the present invention can compensate for the contractile force loss since its thickness becomes thick (increased caliper) when saturated with aqueous body fluid. As a result of this thickening, the portion of the peripheral length of the absorbent article to which the tension band acts increases, thus increasing the stretchability of the elastic member to increase the retraction force provided by the elastic member.

The absorbent core of the present invention may also include a redistribution component capable of redistributing the aqueous body fluid from at least one of the first waist region or the two waist regions of the absorbent article from the crotch region of the absorbent article (adjacent to the wearer's fluid drainage region). have. The absorbent core of the present invention is in effective fluid communication with the supportive waist portion such that when aqueous body fluid is absorbed they redistribute to the expandable supportive waist region.

In another aspect of the invention, the absorbent article has a longitudinal edge connected at least in the waist region instead of the fixation system. This embodiment is useful for training pants, pull-on diapers and the like.

The present invention relates to absorbent products such as diapers, training pants, and urine incontinence patient briefs, and more particularly to provide dynamic fixation around the wearer throughout the wear period of the absorbent product and improved retention for the absorbent product. An absorbent product having a waist portion.

While this specification concludes with the claims specifically pointed out and specifically claimed what constitutes it, it is believed that the invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. Is used to designate substantially the same element.

1 is a plan view of a disposable diaper embodiment of the present invention with the diaper inner surface taken by cutting a portion to show the undercarriage of the diaper facing the viewer.

FIG. 2 is a partially enlarged cross-sectional view of the absorbent insert of FIG. 1 taken along the 2-2 broken line of FIG. 1. FIG.

3 is a partial side view of an infant wearing a disposable diaper aspect of the present invention showing the preferred location of the absorbent core and supportive waist portion on the wearer.

4 is a partial front view of the diaper of the present invention when worn, showing how the supportive waist portion and the core cooperate to prevent slipping or down.

FIG. 5 is a graph of shrinkage force versus time for the elasticized portion of the present invention, showing how the supportive waist portion of the present invention offsets the contractile force loss due to stress relaxation.

As used herein, the term " absorbent product " relates to a device that absorbs and contains body discharges, and more specifically, absorbs and contains various discharges emitted from the body facing or near the wearer's body. Refers to a mechanism to. The term " disposable " is used to denote an absorbent product that is not laundered or restored or reused as an absorbent product (i.e., discarded after a single use, preferably recycled, composted or environmentally acceptable). Discarded in a possible way). &Quot; Integrated form " The absorbent article is formed of separate parts joined together to form a cooperative, eliminating the need for separate operable parts such as holders or liners. A preferred embodiment of the absorbent article of the present invention is the diaper 20 shown in FIG. 1, which is an integral disposable absorbent article. As used herein, the term " diaper " refers to an absorbent article that is worn around the lower buttocks of a generally worn infant and urinary incontinence patient. However, the present invention can also be applied to other absorbent articles such as urine incontinence patient briefs, urinary incontinence patient undergarments, training pants, diaper inserts and the like.

In the simplest form, the absorbent article of the present invention comprises only an outer cover, such as a backsheet (generally relatively liquid-impermeable), an absorbent core connected to the outer cover, a supportive waist portion in effective fluid communication with the absorbent core, and an absorbent material. It is necessary to include means for generating lateral tension through at least a portion of the waist region of the article. The absorbent core can transfer the aqueous body fluid from the crotch region of the absorbent article to at least one waist region. The absorbent core and the backsheet are connected such that the absorbent core is positioned between the backsheet and the wearer's fluid outlet area of the absorbent article. The supportive waist portion prevents longitudinal bending in the waist region of the absorbent article providing supported positioning and fixation. In addition, the supportive waist portion can increase the lateral tension in the waist region of the absorbent article when saturated with aqueous body fluid, thereby offsetting the loss of shrinkage due to the stress relaxation of the internal elastic elements. As used herein, a diaper component may " saturate " into aqueous body fluid after absorbing an amount of aqueous body fluid having a weight of at least eight times that component, or the diaper component is an aqueous body fluid eight times the weight of this component. If it does not absorb, it can be said to be saturated when absorbing more than 50% of the maximum capacity of the aqueous body fluid absorption. Means for generating lateral tension in the waist region provide a force for securing the absorbent article about the waist of the wearer. Examples of such means include, but are not limited to, tape systems containing a landing zone and tape and capable of being elasticized or inelastic, mechanical fastening systems, elasticated side panels and elasticized waist portions, or combinations thereof. It is not limited.

1 is a plan view of a diaper 20 which is a preferred embodiment of the present invention. To more clearly show the structure of the diaper 20, the diaper 20 is shown in a non-constricted state with the inner surface, which is a portion of the diaper cut away and facing the wearer or facing the wearer, oriented toward the viewer. As shown in FIG. 1, the diaper 20 preferably includes a liquid permeable top sheet 24; A liquid impermeable backsheet 26 connected to the topsheet 24; An absorbent core 28 positioned between the top sheet 24 and the back sheet 26; Elasticized leg cuffs 32; Elasticized waist portion 34; Fixation system 36 specified in various places; And a retaining combination 22 comprising a supportive waist portion 38. The diaper 20 of the preferred embodiment of the present invention shown in FIG. 1 includes side panel pairs 30, 40 that are laterally extended in connection with the retention combination 22. In the most preferred aspect of the invention, at least a portion of the side panel pair 40 is elasticized.

An outer surface 64, an inner surface 60 opposite the outer surface 64, a first waist region, a second waist region 44 opposite the first waist region 42, a first waist region 42. A diaper 20 having a crotch region 46 positioned between the second waist region 44 and between the longitudinal edge 54 and the distal edge 56 is shown in FIG. 1. The inner surface 60 of the diaper 20 includes a portion of the diaper 20 positioned adjacent to the wearer's body during use (ie, the inner surface 60 generally includes at least a portion of the top sheet 24, and the top sheet). Formed by other components linked to 24). The outer surface 64 includes a portion of the diaper 20 positioned outward from the wearer's body (ie, the outer surface 64 is generally formed by a portion of the backsheet 26 and other components connected to the backsheet 26). Is formed).

The diaper 20 also has two centerlines, a longitudinal centerline 100 and a transverse centerline 102. As used herein, the term " longitudinal " generally refers to a diaper 20 plane that is aligned (approximately parallel) with a vertical plane that divides the standing wearer into left and right halves when the diaper 20 is worn. Refers to the line, axis, or direction at As used herein, " lateral direction " The terms " lateral " can be used interchangeably and refer to a line, axis or direction lying on the diaper plane generally perpendicular to the vertical direction (i.e., dividing the wearer into front and rear halves).

A retaining assembly 22 is shown in FIG. 1 with a perimeter 50 defined by an outer edge of the retaining assembly 22, whose longitudinal edge is designated 52. The perimeter 50 of the retaining combination 22 further includes a portion of the diaper end edge 56 lying laterally between the longitudinal edges 52.

1 shows a preferred embodiment of a diaper 20 in which the top sheet 24 and the back sheet 26 have generally larger length and width dimensions than the absorbent core 28. The top sheet 24 and the back sheet 26 extend beyond the edge of the absorbent core 28 to form the periphery 50 of the retaining assembly 22. The topsheet 24, backsheet 26 and absorbent core 28 can be assembled in various well known forms, while the preferred diaper form is generally US patent issued to Buell on January 14, 1975. 3,860,003 and U.S. Patent No. 5,151,092 to Buell et al. On September 29, 1992, which are incorporated herein by reference.

FIG. 2 is an exploded cross-sectional view of the diaper 20 taken along line 2-2 of FIG. 1 to show the supportive waist portion 38 in detail. As shown in FIG. 2, a preferred embodiment of the supportable waist portion 38 is an extension of the fluid redistribution component 29 and includes three absorbent foam layers 39a-39c. Also shown is absorbent core 28, fluid capture component 27 and fluid redistribution component 29. A waist shield 37 is also shown, which is located between the supportive waist portion 38 and the topsheet 24.

Absorbent core 28 is generally compressible, compliant, non-irritating to the wearer's skin, and may include absorbing means capable of absorbing and retaining liquids, such as urine and other specific body discharges. As shown in FIG. 1, the absorbent core 28 includes a garment surface, a body surface, side edges, a first waist region 58a and a second waist region 58b. Absorbent core 28 may be manufactured in a wide range of sizes and shapes using liquid absorbent materials (eg, pulverized pulp material, commonly referred to as air felt) commonly used in disposable diapers and other absorbent articles ( For example, rectangular, pavilion, " T ", asymmetrical, etc.). Examples of other suitable absorbents include clotted cellulose cotton; Melt blown polymers containing co-foams; Nonwovens such as nonwovens formed using capillary fibers; Chemically reinforced, modified or crosslinked cellulose fibers; Tissue including tissue sheaths and tissue laminates; Absorbent foams; Absorbent sponges; Superabsorbent polymers; Absorbent gelling materials; Or equivalent materials thereof or mixtures thereof. In addition, the shape and structure of the absorbent core may be modified (e.g., the absorbent core may include various caliper bands, hydrophilic gradients, superabsorbent gradients or lower average density and lower average basis weight acquisition zones, or One or more layers or structures). However, the overall absorbent capacity of the absorbent core 28 should be consistent with the loading design and intended purpose of the diaper 20. In addition, the size and absorbent capacity of the absorbent core 28 may vary to accommodate the wearer from infant to adult. In addition, the first waist edge 58a of the absorbent core 28 should be in effective fluid communication with the supportive waist portion 38 of the diaper 20. The term effective fluid communication herein is intended to mean that aqueous body fluids, in particular, urine, may be distributed from one component of the diaper 20 to another by capillary attraction, osmotic attraction or other liquid transfer mechanism. The absorbent core 28 must be capable of dispersing sufficient liquid in the supportive waist portion 38 so that the supportive waist portion 38 can expand when wetted by the liquid. Examples of absorbent structures for use as absorbent cores 28 are described in US Pat. No. 4,610,078 issued to Weisman et al. On September 9, 1986, and Angstadt, December 19, 1989. US Patent No. 4,834,735 to Alemany et al. On May 30, 1989, and US Patent No. 5,318,554 to Young et al. On June 7, 1994. have. Each of these documents is incorporated herein by reference.

Vertical wicking, ie, liquid wicking in the direction opposite to gravity, is a particularly desirable performance for the absorbent core described herein. This is because the absorbent core is often used in absorbent products in such a way that the aqueous body fluid to be absorbed moves in the product from a relatively low position to a relatively high position within the absorbent core of the product. For example, the diaper 20 of the present invention also includes a supportive waist portion 38, which will be described in detail below, wherein the supportable waist portion 38 is resistant to bending in the longitudinal direction when saturated with aqueous body fluids. The volume is increased while providing increased lateral tension in the waist regions 42, 44 to compensate for the increased resistance to and the loss of lateral tension due to the stress relaxation of the elastic element of the diaper 20. The absorbent core 28 provides aqueous fluid that can be absorbed in the crotch region 46 so that the swelling feature of the supportive waist portion can act over the entire range of wearer movements in the first waist region 42, the second waist region. It should be possible to redistribute it into one or two of (44). Thus, the vertical wicking force enables such redistribution when, for example, the waist regions 42, 44 are relatively higher than the crotch region 46 (eg, when the wearer sits or stands up). A method of measuring the vertical wicking properties of a diaper core component is disclosed in the TEST METHOD section of co-pending US Patent No. 07 / 989,270, filed December 11, 1992, which application is incorporated herein by reference. Was used.

As shown in FIG. 2, a particularly preferred embodiment of the absorbent core 28 includes a fluid capture component 27 and a fluid redistribution component 29. Fluid capture component 27 may include any porous hydrophilic material that absorbs and distributes aqueous body fluids. Such absorbent materials are frequently foam-containing or fiber-containing materials in nature. As long as the fluid redistribution component 29, alone or in combination with the capture component 27, provides an absorbent core 28 having vertical wicking properties that enable the inflation characteristics of the supportive waist portion 38. Fluid redistribution component 29 may include any of the materials discussed above suitable for absorbent core 28.

Preferred embodiments of the fluid redistribution component 29 include at least one layer of absorbent foam material disclosed in US Pat. No. 5,268,224, issued December 7, 1993 to DesMaris et al., Which is incorporated herein by reference. Used as literature. Absorbent foam materials of the type disclosed above are preferably prepared by polymerizing a high dispersion water-in-oil emulsion (HIPE foam). They typically have a free absorption capacity of about 20 to about 100 ml / g and a specific surface area per foam volume of at least about 0.025 m 2 / cc. As used herein, the term " free absorbing capacity " refers to the total amount of test fluid (Jayco synthetic urine) in which a given foam sample is absorbed into the cytoplasmic structure per unit mass of solid material in the sample, and " ratio per foam volume. &Quot; Surface area " refers to the capillary suction specific surface area of the foam structure in the expanded state multiplied by the foam density. To be particularly useful in absorbent products for absorbing urine, preferred absorbent foams of the present invention are generally at least about 24.1 cm (9.5 in), preferably at least about 30 cm (11.8 in), most preferably about 40 cm ( Capillary absorption pressure of about 15.7 inches) or more. The term " capillary absorption pressure " as used herein is the height when the vertical leak absorption capacity is 50% of the free absorption capacity. Methods of measuring most of these properties are described in the Test Methods section of US Patent Application No. 07 / 989,270 (Dyer et al.), Filed December 11, 1992, which application is herein incorporated by reference. Used as literature. The procedure for measuring the free absorbent capacity of the foam is described in the later section of the test method.

The particularly preferred absorbent core 28 shown in FIG. 2 has a fluid redistribution component 29 comprising the three HIPE foam layers described above. Further details of this type of absorbent core 28 are disclosed in US Pat. No. 5,318,554, issued June 7, 1994 to Young et al., Which is incorporated herein by reference.

Such preferred absorbent foam structures are frequently used in absorbent articles together with other forms of absorbent structures that may also participate in the acquisition, distribution and / or storage of aqueous fluids. In this regard, the absorbent foam structure herein serves primarily as a fluid redistribution component in the absorbent article, which foam absorbs the aqueous body fluid from other absorbent components, such as the capture component, which absorbs the fluid. It is desirable to have a tendency to attract to. This tendency to drain fluid from other absorbent product components is known in the art as " distribution ". Some concepts for measuring dispensing concepts and dispensing performance are disclosed, for example, in US Pat. No. 4,610,678, supra. When testing dispensing performance using procedures similar to those disclosed in US Pat. No. 4,610,678, these preferred absorbent foam structures exhibit particularly desirable fluid dispensing properties.

The backsheet 26 is located adjacent to the garment surface of the absorbent core 28. The back sheet 26 prevents the discharged and absorbed substances contained in the absorbent core 28 from wetting bedding and underwear, which are products in contact with the diaper 20.

The backsheet 26 is generally impermeable to aqueous body fluids (eg, urine) and is preferably made of a thin plastic film, while other flexible liquid impermeable materials may also be used. The term " flexible " as used herein refers to a material that is compliant and easily conforms to the general shape and contour of the human body. Thus, the backsheet 26 may comprise a composite material such as a woven fabric, a nonwoven fabric, a polymeric film such as a thermoset film of polyethylene or polypropylene, or a film coated nonwoven fabric. Preferably the backsheet is a thermosetting film having a thickness of about 0.012 mm (0.5 mil) to about 0.051 mm (2.0 mil). Particularly preferred materials for backsheets include RR8220 blown films and RR5475 mold films made by Tredegar Industries, Inc. of Terrejote, India. The backsheet 26 is preferably embossed and / or mated to provide a more similar form to the fabric. The backsheet 26 also allows gas to escape from the absorbent core 28 (ie, breathable) while preventing the emissions from penetrating the backsheet 26.

The topsheet 24 is located adjacent the body surface of the absorbent core 28 and is preferably connected to the backsheet 26 by attachment means (not shown) well known in the art. For example, the top sheet 24 may be secured to the back sheet 26 by a uniform continuous adhesive layer, a patterned adhesive layer, or an arrangement of separate adhesive lines, spiral adhesive lines, or adhesive points. Adhesives that are known to be satisfactory are available from HL-1258 and Findley Adhesives Wauwatosa, Wisconsin, manufactured by H.B. Fuller Compony, St. Paul, Minn. Manufactured and commercially available H2031. The attachment means preferably comprise an adhesive of an opening pattern filament network, such as disclosed in US Pat. No. 4,573,986 to Minetola et al. On March 4, 1986, which is incorporated herein by reference. Was used. Alternatively, the attachment means may comprise thermal bonds, pressure bonds, ultraviolet bonds, power mechanical bonds or any other suitable attachment means known in the art or a combination of such attachment means. The term " linked " as used herein refers to a form in which one element is directly fixed to another element by directly attaching it to another element, and that one element is attached to another element by attaching it to an intermediate member attached to the other element. Indirectly fixed forms and forms of securing one element in a defined position around another element without being fixed directly or indirectly to another element. In a preferred embodiment of the invention, the topsheet 24 and the backsheet 26 are connected to each other at the periphery 50 of the retaining assembly 22 by attachment means (not shown), and the absorbent core 28 is In the meantime it is bound. That is, the absorbent core 28 is " floating " between the top sheet 24 and the back sheet 26.

The top sheet 24 is compliant, has good feel, and is non-irritating to the wearer's skin. The topsheet 24 is also liquid permeable to allow aqueous body fluids (e.g., urine) to penetrate the thickness easily. Suitable topsheets include a wide variety of materials such as porous foams; Reticulated foam; Perforated plastic film; Or from woven or nonwoven webs of natural fibers (eg, wood or cotton fibers), synthetic fibers (eg, polyester or polypropylene fibers), or mixtures of natural and synthetic fibers. The topsheet 24 is preferably made of a substantially hydrophobic material to isolate the wearer's skin from the liquid contained in the absorbent core 28. There are many manufacturing methods that can be used to make the topsheet 24. For example, the topsheet 24 may be a nonwoven web of spunbonding, consumable, wet laminate, meltblown, hydroentangled fibers or combinations thereof. Preferred topsheets can be consumed and thermally bonded by methods well known to those skilled in the fiber art. Preferred topsheets are short-length polypropylene fiber webs, such as those designated as P-8 manufactured by Veratec, Inc., an International Paper Company company in Walpole, Massachusetts. It includes.

The diaper 20 preferably further includes an elasticized leg cuff 32 to provide improved retention of liquids and other body discharges. Each elasticized leg cuff 32 may include several other aspects to reduce leakage of body discharge in the leg area (leg cuffs may be leg bands, side flaps, blocking cuffs or elasticized cuffs) , Also sometimes referred to as above). U. S. Patent No. 3,860, 003 describes a disposable diaper which provides a retractable leg opening with side flaps and one or more elastic members for providing elasticized leg cuffs (gasket cuffs). US Patent No. 4,909,803, issued to Aziz et al. On March 20, 1990, describes " standing up " Disclosed is a disposable diaper with an elasticized flap (blocking cuff). US Pat. No. 4,695,278, issued to Lawson on September 22, 1987, discloses disposable diapers having double cuffs, including gasket cuffs and blocking cuffs. Each elasticized leg cuff 32 may be formed to resemble any of the leg bands, side flaps, blocking cuffs or any of the aforementioned elasticized cuffs, while each elasticized leg cuff 32 is It is preferred to include two elongated cuffs as described in commonly granted PCT patent application WO 94/18927 published September 1, 1994, which is incorporated herein by reference.

The diaper 20 may further include an elasticized waist portion 34 that provides improved fixation and retention. The elasticized waist portion 34 is a portion or zone of the diaper 20 that is designed to elastically expand and contract so as to be dynamically fixed to the wearer's waist. In the preferred embodiment of the present invention shown in FIG. 1, the elasticized waist portion 34 extends longitudinally inward from the diaper end edge 56 located in the second waist region 44 to extend the diaper end edge 56. The second waist edge 58b of the absorbent core 28 forms at least a portion and is located in the second waist region 44. The elasticized waist portion or any component thereof may include a separate element attached to the diaper 20, while the elasticized waist portion 34 preferably is a backsheet 26 or topsheet 24. ), Preferably an extension of other elements of the diaper, such as both the backsheet 26 and the topsheet 24.

The elasticized waist portion 34 can be constructed in many different forms, including those described in US Pat. No. 4,515,595 and US Pat. No. 5,151,092, each of which is incorporated herein by reference.

The diaper 20 also maintains the first waist region 42 and the second waist region 44 in an overlapping form so that side closures that hold the diaper on the wearer by maintaining lateral tension around the diaper's peripheral length A fastening system 36 to form. Examples of sticking systems include U.S. Patent 4,846,815 to Scripps, July 11, 1989, U.S. Patent 4,894,060 to Nestegard, January 16, 1990, and August 1990. US Pat. No. 4,946,527, issued to Batrell, dated 7, US Pat. No. 3,848,594, issued to Buell, November 19, 1974; and US, Hirotsu, issued May 5, 1987. Patent Application B1 4,662,875, each of which is incorporated herein by reference. Any fixation system described above may be suitable for the diaper 20 of the present invention. A preferred aspect of the fixation system 36 should be prepared for the lateral tension bands to penetrate the supportive waist portion 38 around the diaper's peripheral length. Such a preferred fastening system 36 may comprise tape or mechanical fastening means. For example, a suitable fastening system 36 includes a tape tab, a release portion to protect the adhesive on the tape tab, and a landing zone, where the tape tab is formed of the first waist region 42 or the first waist region 42. Located in one of the two waist regions 44, preferably in the second waist region 44 adjacent the distal edge 56, the landing zone is either the first waist region 42 or the other of the second waist regions 44. , Preferably in a first waist region 42 adjacent the distal edge 56.

The diaper 20 shown in FIG. 1 preferably further comprises a side panel 30 of the first waist region 42 and a side panel 40 of the second waist region 44. These side panels 30, 40 may be formed from extensions of the top sheet 24, the back sheet 26, or both. The side panels 30, 40 preferably comprise a discontinuous member connected to and extending laterally outwardly from the retaining combination 22 longitudinal edges 52 in at least each of the waist regions 42, 44. do. Some of the side panels 30, 40 may be connected to and extend further laterally outwardly from the longitudinal edges 52 of each of the retention combinations 22 in the crotch region 46. The side panels 30, 40 may be connected to the retaining combination 22 by any method known in the art. For example, the side panels 30, 40 may be connected to the retaining combination 22 by a uniform and continuous adhesive layer, a patterned adhesive layer, or a line of adhesive, spiral bond or adhesive point. An adhesive known to be satisfactory is manufactured by H. B. Fuller Co., St. Paul, Minnesota and marketed under HL-1258. The attachment means preferably comprises an adhesive of an opening pattern filament network structure as disclosed in US Pat. No. 4,573,986 to Minnetola et al. On March 4, 1986, more preferably as of October 7, 1975. U.S. Patent No. 3,911,173 to Sprague Jr., U.S. Patent No. 4,785,996 to Ziecker et al. On November 22, 1978, and Berenikz on June 27, 1989. As illustrated in the apparatus and method shown in US Pat. No. 4,842,666 to Werenicz, words in a spiral pattern comprise several adhesive filament lines. Each of these applications is used herein by reference. Alternatively, the attachment means may comprise thermal coupling, pressure coupling, ultrasonic coupling, power mechanical coupling or any other suitable attachment means known in the art or a combination of such attachment means.

Side panels 30 and 40 can be made from any material conventional in the art. For example, the side panels 30 and 40 can be made from thin flexible plastic films, porous foams, woven webs or nonwoven webs of natural or synthetic fibers. Side panels 30 and 40 can be made from laminates incorporating such materials. Particularly preferred materials used for the side panels 30, 40 are short length polypropylene fibers, such as those manufactured by Veratech Incorporated, an affiliate of International Paper Company of Walpole, Massachusetts, designated P-8. Non-woven web laminates of, and thin thermosetting films such as RR8220 blown films and RR5475 mold films made by Tredega Industries, Inc., Terrejote, India.

In a more preferred aspect of the invention, the side panel 30 of the first waist region 42, or preferably the side panel 40 of the second waist region 44 is elasticized. The elasticized panels cause the diaper sides to expand and contract, thus making the elastic panels more comfortable by initially fixing the diaper comfortably to the wearer and supporting retention throughout the wear time sufficiently past the discharge on the diaper. The elasticized panel provides an elasticized extension that provides comfort and fit to the body. Even when the diaper wearer pulls one elasticized panel more than the other panel during application (asymmetric application), the diaper 20 is " adjusted " while worn, so that the elasticized panel is It further provides more effective applications. The diaper 20 of this preferred aspect of the invention preferably has an elasticized panel operatively associated with the side panel 40 located in the second waist region 44, whereas the diaper 20 alternatively An elasticized side panel can be provided that is located in the first waist region 42, or in both the first waist region 42 and the second waist region 44.

While elasticized panels can be constructed in many forms, a U.S. patent for example of a diaper with an elasticized panel located on the ear (ear flap) of the diaper is issued to Wood et al. On August 15, 1989. 4,857,067, US Patent No. 4,381,781 to Sciaraffa et al. On May 3, 1983; US Patent No. 4,983,753 to Van Gompel on July 3, 1990, 10, 1994. US Patent No. 5,358,500, issued to LaVon on March 25, and US Patent No. 5,151,092, supra, each of which is incorporated herein by reference. For example, the elasticized panel can include a laminate of nonwoven webs, elastic members, and thin flexible thermoplastic films. Suitable materials for nonwoven webs and flexible thermoplastic films are described above with respect to top sheet 24 and back sheet 26, respectively. Suitable materials for elastic members are made of EXX 550 from Exxon Chemical Compony, Leut Zurich, Illinois. This laminate is then subjected to mechanical stretching sufficient to permanently stretch the nonwoven web and thermoset film using procedures such as those described in US Pat. No. 5,151,092, to form an elasticized panel. Alternatively, the inelastic portions of the side panels can be collected before joining them with the elastic member.

Preferred elasticized panels include film (SELF) webs that are structurally similar to elastic. Structurally similar film webs are extensible materials that exhibit an elastic-like aspect in the stretch direction without using an added elastic material. SELF webs include deformable networks having two or more adjacent, discontinuous and dissimilar regions. One of the regions is formed so as to exhibit a resistance to applied axial stretching in a direction parallel to the predetermined axis before most of the other region develops significant resistance to applied stretching. At least one of the regions has a surface length that is much greater than the surface length of the other regions when measured substantially parallel to the predetermined axis, while the material is in an untensioned state. Regions exhibiting longer surface lengths include one or more variations extending beyond the plane of another region. SELF webs exhibit significantly different stages of two or more controlled regulating forces and thus stretch along one or more predetermined axes when stretching is applied in a direction parallel to the predetermined axis. After the web exhibits a first resistance to the applied stretch until the stretch of the SELF web is sufficient to introduce most of the region with a longer surface length into the applied stretch plane, the SELF web has a second resist to further stretch. Indicates. The total resistance to stretching is higher than the first resistance to stretching provided by the first region. SELF webs suitable for the present invention are described in more detail in co-pending commonly issued US patent application Ser. No. 08 / 203,456, filed by Donald C. Roe et al. On Feb. 24, 1994, which is incorporated herein by reference. It is used herein by reference.

As shown in FIG. 2, the diaper 20 further includes a waist shield 37. The waist shield 37 is provided to prevent leakage of aqueous body fluid through the topsheet 24 from the supportive waist portion 38 (described in detail below). In the preferred embodiment of the present invention shown in FIGS. 1 and 2, the waist shield is secured to the topsheet 24 in the waist region 42 of the diaper 20. Also, in a more general case, the waist shield 37 is secured to the topsheet 24 in any waist region of the diaper 20 containing the supportive waist portion 38. The waist shield 37 extends outwardly longitudinally from slightly below the waist edge 58a of the absorbent core 28, with the waist shield 37 positioned at the first waist region 42 of the diaper end edge 56. Partially apply one transverse edge of the absorbent core 28 to the capture component 27. This type of waist shield is discussed in more detail in US Pat. No. 4,578,071, issued to Buell on March 25, 1986, which is incorporated herein by reference.

The lumbar shield 37 is impermeable to aqueous body fluids. While preferably made from thin plastic films, other flexible liquid impermeable materials can be used. Thus, the waist shield 37 may comprise a material having properties that are essentially the same as those suitable for the backsheet 26. Preferred materials for the waist shield 37 are thermoplastic films having a thickness of about 0.012 mm (0.5 mil) to about 0.051 mm (2.0 mil).

The diaper 20 further includes a supportive waist portion 38. As used herein, the term supportive waist portion may be located in the first waist region 42, the second waist region 44, or both of the waist regions to cause loss of fixation at the waist due to one or more of the above-described failure modalities, or Means the diaper 20 component to prevent premature leakage. In a preferred embodiment of the diaper 20 of the present invention shown in FIGS. 1 and 2, the supportive waist portion 38 extends a portion of the absorbent core 28 into the first waist region 42 of the diaper 20. It is shown. Most preferably the supportive waist portion 38 is longitudinally adjacent the transverse edge 56 in the first waist region 42 of the diaper 20 at the first waist edge 58a of the absorbent core 28. Extends to position. Alternatively, the diaper of the present invention may have a supportive waist portion located in the second waist region 44, or both waist regions 42, 44. At a minimum, the supportable waist portion 38 passes from the distal edge 58a or 58b of the core 28 through a tension band provided in the waist region by the fixation system 36 to the first waist region 42 or the second. It should extend longitudinally to the waist region 44. In addition, the supportive waist portion of the present invention is considered to include an extension of the absorbent core 28 or one or more separate elements, which separate elements are in effective fluid communication with the absorbent core 28 or both.

As illustrated in FIG. 2, the preferred supportable waist portion 38 comprises an absorbent foam having one or more layers of material, preferably the properties disclosed in US Pat. No. 5,268,224. In the preferred embodiment shown in FIG. 2, the supportable waist portion 38 includes three foam layers 39a-39c. These layers 39a-39c are typically not connected by an adhesive and are in effective fluid communication with each other and also in fluid communication with the fluid capture component 27 as they are simply extensions of the fluid redistribution component 29.

The supportive waist portion 38 should have a physical or chemical property that offsets at least some of the negative effects of various modalities that cause loss of fixation or premature leakage due to sagging, peeling or curling exhibited by current diapers. do.

In the simplest form, for example, only the lateral tension is generated in the waist region of the topsheet 24, the backsheet 26, the core 28, the elasticized leg cuffs 32, the fixation system 36, and the like. In diapers that include the means and the supportable waist portion 38, the supportive waist portion 38 is improved when compared to a similarly structured absorbent product having an elastic waistband of the present technology instead of the supportable waist portion 38. Provide fixation and retention.

An advantage of the absorbent article of the present invention is that it provides resistance to loss of retention and retention due to curling, slipping / peeling or sagging / breaking. In the case of wearing absorbent products, the core material falls from the waist region to the crotch region of the absorbent product due to the decrease in the stiffness of the waist region caused by the repeated application of force, which occurs during normal wearing. The contribution is substantially eliminated. Specifically, the supportive waist portion 38 provides an enhanced rigid component, which component offsets the force even after repeated application of a force that tends to produce curling, slipping or sagging / breaking that is applied during normal wear. To provide bending resistance. In the absence of these rigid components, abdominal dilation pushes the absorbent product away from the upper waist of the absorbent product and causes it to dry or face down.

For example, one measure of the stiffness component is the cantilever bending value. A supportive waist portion 38 having a dry cantilever bend value of at least about 8.3 inches (3.3 inches) and preferably at least about 9.4 inches (3.7 inches) is satisfactory to offset bending when the absorbent article is dry or partially wet. It has been found to provide resistance. Importantly, when the supportive waist portion 38 is saturated with aqueous body fluid, i.e., when the risk of leakage from the waist is greatest, the supportive waist portion 38 is resistant to curling and the diaper 20 is dry. Keep the same resistance. The resistance to curling when wet is at least about 9.9 cm (3.9 in), preferably at least about 10.7 cm (4.2 in) when the supportive waist portion 38 of the present invention is saturated with synthetic aqueous body fluids. Preferably by a cantilever bending value that increases by greater than about 11.6 cm (4.6 inches). Methods of measuring dry cantilever bend values and saturated cantilever bend values are provided in the test methods below.

The change in stiffness when wet with aqueous body fluid can be seen more clearly if it is defined in terms of cantilever bending ratio. As used herein, the term " cantilever bending ratio " is defined as the ratio of the cantilever bending value when the absorbent product is saturated with synthetic aqueous body fluid to the cantilever bending value when the absorbent product is dry. Absorbent articles of the invention are known to have a cantilever bending ratio of about 1.0: 1 or more. The absorbent article of the present invention having such a minimum cantilever bending ratio maintains at least dry stiffness in the waist region when saturated with synthetic aqueous body fluids. Preferably the cantilever bending ratio for the absorbent article of the present invention is at least 1.1: 1, most preferably at least 1.3: 1. That is, preferred embodiments of the absorbent articles of the present invention increase their stiffness when they are saturated with synthetic aqueous body fluids.

In addition, the bending resistance is maintained even when the supportive waist portion 38 is bent for several times. For example, the dry cantilever bend value is greater than about 8.0 cm (3.5 inches) after the supportive waist portion 38 is bent periodically. If this test is repeated when the supportive waist portion 38 is saturated with synthetic aqueous body fluid, the cantilever bending value is at least about 9.6 cm (3.8 in), preferably at least about 11.1 cm (4.4 in). A method of measuring stiffness retention for periodic flexion is provided in the test method below.

Rigid reserves can also be defined. As used herein, the term " rigid retention ratio " is defined as the ratio of the flexion flexure values measured for the same sample before and after the sample is flexed periodically for 20 cycles (see test method). This rigid retention can be calculated for dry samples or samples saturated with synthetic aqueous body fluids. The supportive waist portion of the present invention has a rigid retention ratio of at least about 0.90, preferably at least about 0.95 when dried. If the sample is saturated with synthetic aqueous body fluid, the rigid retention ratio is at least about 0.88, preferably at least about 0.92.

The supportable waist portion 38 and the absorbent core 28 of the present invention may also act simultaneously so that a general body movement or absorbent product is loaded with body discharge even in the case of a simple absorbent product without the elasticized waist portion or side panel described above. The downward force generated in the case provides resistance to assist in the prevention of downward movement. This simultaneous action is shown in FIGS. 3 and 4, which represent an infant wearer of the diaper aspect of the present invention.

As can be seen in the figure, the minimum peripheral length 85 around the infant wearer follows a line around the infant wearer connected to the point of the abdominal folds and back waist which is slightly below the abdomen. For example, the lateral tension band provided by the fixation system 36 moves from the portion 80 of the diaper's waistband to which it is applied (typically around the wearer's waist over or near the wearer's navel and abdominal folds). Even when placed on the line of the peripheral length 85, it is said to go down. The tension bands are pre-processed to move towards the line of minimum peripheral length 85 because this reduces the tension.

As in the preferred embodiment of the invention shown in FIGS. 1 and 2, when the supportive waist portion 38 is an extension of the absorbent core 28 or is integral with the absorbent core 28, the two components of the diaper are simultaneously Acts to dissipate forces F ₁ due to normal wearer movement or loading of body discharges, and if not so, the forces F ₁ provide resistance F ₂ at the wearer's legs to lower the diaper down. It works to let go. That is, the supportive waist portion 38 and the absorbent core 28 act as a " base " to transfer the force from the diaper waist region to the wearer leg. This co-action is illustrated in FIG. If the core components of the current absorbent articles are saturated with aqueous body fluids, the loss of mechanical integrity prevents this synergy.

In addition, an absorbent article is provided with an elastic portion for assisting the provision of lateral tension in the waist region of the diaper 20, for example the elasticized side panel 40 of the preferred aspect of the invention shown in FIG. In this case, the supportive waist portion 38 provides an additional advantage of compensating for stress relaxation in the polymerization system used as the elastic member in the elasticized portion. As explained in more detail below, the caliper of the supportive waist portion 38 increases when the supportive waist portion 38 is saturated with aqueous body fluid. This increase in caliper increases the peripheral length of the overall absorbent article at the waist, thus stretching the elasticized portion of the waist region of the absorbent article to compensate for stress relaxation with the increased retraction force caused by the stretching of the elasticized portion.

Figure 5 shows a schematic diagram showing the change in the contraction force in the tension band of the waist region of the diaper 20, which is a preferred embodiment of the present invention. When the diaper 20 is applied to the wearer, the retraction force is measured by the amount of stretching provided to the elastic element of the waist region during the application of forming the tension band. This is seen in the first part of FIG. 5 where the retracting force essentially goes from zero to a maximum over a very short time (i.e., during application the elastic element is rapidly drawn up to the given elongation and then the elongation is secured by the fixation system). do). Over time, the contractile force at the waist decreases substantially due to stress relaxation. This reduced contraction force can cause the diaper waist area to open, resulting in loss of fixation and increased risk of leakage at the waist because the contractile force in the tension band is reduced.

However, for the absorbent article of the present invention, the supportive waist portion 38 compensates for the contractile force loss due to stress relaxation. Compensation for the contractile force loss due to this stress relaxation is shown in the second part of FIG. 5 by the second weighting of the contractive force over a very short time. The supportive waist portion 38 compensates for stress relaxation by effectively increasing the degree of stretching of the elastic elements in the tension bands around the perimeter of the absorbent article.

Supportive waist portion 38 compensates for stress relaxation by increasing calipers when exposed to aqueous body fluids. When the supportive waist portion is exposed to aqueous body fluids (i.e. wet), the only direction to increase the caliper is away from the wearer (i.e. the wearer's waist is not substantially compressed by the caliper increase), so The diameter is increased by caliper increase and any lateral expansion that can occur. This effectively increases the peripheral length of the absorbent article around the wearer's waist, thus further stretching the elastic element. Mathematically, this increase may be referred to as an increase in the caliper by the supportive waist portion 38 of the Xmm amount averaged over both the full length of the tension bands, causing the elastic element of the absorbent article to further stretch about 2_Xmm. . For example, a caliper increase of about 1 mm (˜0.04 inch) stretches an elastic element of about 6 mm (˜0.25 inch). The resulting increase in shrinkage in the tension band depends on the specific stress / strain characteristics of the polymerization system used as the elasticized member.

In order to ensure that the supportive waist portion 38 of the present invention makes up for the significant portion of shrinkage loss due to stress relaxation, the supportive waist portion of the present invention is at least 3.0: 1, preferably at least 5.0: 1, most preferably Has a caliper increase ratio of 7.0: 1 or greater. As used herein, the term " caliper increase ratio " refers to the caliper versus dry state of the supportive waist portion 38 (ie, fully contracted) when fully saturated with synthetic aqueous body fluid (i.e., fully inflated). Refers to the ratio of the caliper of the supportive waist portion. For example, in the most preferred embodiment, the supportive waist portion of the present invention has a dry caliper of about 1.5 mm and a wet caliper of 13.8 mm, with a caliper increase ratio of 9.2: 1. Methods of measuring the caliper (wet caliper) in the fully expanded state and the caliper (dry caliper) in the fully retracted state are provided in the test method section below.

The supportive waist portion 38 of the present invention also compensates for the reduced lateral tension in the waist region due to causes other than stress relaxation of the elastic elements described above. Examples of other causes of reduced lateral tension in the waist region include stretching of inelastic elements at the waist and peeling of the fixation system 36. In this case, the effective peripheral length of the diaper 20 increases around the wearer's waist and the lateral tension in the waist region decreases. As noted above, by increasing the caliper when saturated with aqueous body fluid, the supportive waist portion 38 of the present invention provides a force opposite the wearer's waist, resulting in a side retightening the diaper around the wearer's waist. An annular stress is generated in the waist region of the diaper 20 to compensate for the directional tension loss.

The supportive waist portion 38 of the present invention not only increases the caliper when saturated with aqueous body fluid as described above, but also when the supportive waist portion 38 exerts force generated during use, such as a compressive force in the tension band. The caliper must also be increased. That is, the expansion force caused by the increase in the caliper of the supportive waist portion 38 is greater than the compressive force in the tension band so that the supportive waist portion 38 must compensate for stress relaxation. One measure of resistance to compression is resistance to compression deflection. Resistance to compression deflection can be quantified for the present invention by measuring the amount of stress produced in the foam sample (% caliper reduction), wherein the foam sample is subjected to a stress in the form of 0.74 psi (5.1 kPa) which limits the pressure. Later it is saturated with synthetic urine and fully expanded. Preferred embodiments of the supportive waist portion 38 of the present invention have a resistance to compression deflection of less than about 40%. The method of measuring the resistance to compression deflection is briefly described in the following test method and also described in detail in the above-mentioned US Patent No. 07 / 989,207.

While the physical properties of the supportable waist portion 38 may be provided by a preferred absorbent foam material, for example HIPE foam, for at least a portion of the absorbent core 28 of the present invention, anything mentioned herein may be It is not intended to be limited only to these materials. The supportive waist portion 38 of the present invention has a caliper increase when wet (ie, a caliper increase ratio of at least 3.0: 1), a dry cantilever bend value as described above, and a wet cantilever bend value (ie, cantilever bend at least 1.0: 1). Value), or both, or combinations of these materials. For example, supportive waist portion 38 may include two components: a rigid element that provides resistance to bending and another that provides replenishment for stress relaxation in the elastic element of the absorbent article. Spin-crossed polyethylene foams available under the Volara trade name from Voltec Inc., Lawrence, Mass., Are suitable as rigid elements. An inflatable spacer similar to the spacer disclosed in US Pat. No. 5,330,459, issued to LaVon et al. On July 19, 1994, can compensate for stress relaxation in elastic elements by providing caliper increases when wet, This document is used herein by reference. For example, the inflatable spacer described herein increases to a thickness of at least 10 times, more preferably at least 50 times, the unexpanded thickness. Aspects are also envisioned that have a waist portion that provides only stiffness or provides only a caliper.

The diaper 20 preferably places one of the waist regions, preferably the second waist region 44, below the wearer's back and draws the rest of the diaper between the wearer's legs, so that the other waist region, preferably the first The waist region 42 is applied to the wearer by positioning it across the front of the wearer. The tape tab of fixation system 36 is then dissociated from the dissociation portion of the fixation system. The diaper then attaches one of the tape tabs to its corresponding landing zone and then pulls the remaining tape tab to attach to the landing zone. The elasticized side panels are typically extended and tensioned during this operation to match the size and shape of the wearer.

In another aspect of the invention useful as a training pant or pull-on diaper, a portion of the longitudinal edge 54 of the diaper 20 lying on the waist regions 42, 44 lies in the crotch region 46. It extends laterally outward of a portion of the directional edge 54. That is, in another aspect, the diaper is wider at the waist regions 42, 44 than the crotch region 46. It also connects the longitudinal edges 54 of the waist regions 42, 44. That is, in this other aspect of the invention the absorbent article is not provided with a fixation system. In addition, a lateral tension band is provided in the waist region of another aspect of the invention by an elasticized portion, for example an elasticized side panel. That is, the diaper 20 is folded around its transverse centerline 102 such that the first waist region 42 faces the second waist region 44. Then, the opposing longitudinal edges 54 of the diaper 20 in each of the first waist region 42 and the second waist region 44 are connected to the molded suture by means conventional to the art. Depending on the lateral width of the first waist region 42 rather than the second waist region 44, these sutures may be located on the front, side or even back side of another aspect when the absorbent article is worn. An example of a means of joining the edges to the forming sutures is provided in US Pat. No. 5,236,430 to Bridges, dated August 17, 1993, which is incorporated herein by reference.

Test Methods

In the description of the present invention, many features are set. As reported, the above characteristics can be measured using the following test fluids and test methods.

1) Test fluid-synthetic urine

Several measurements described in the tests herein involve the use of test fluids such as synthetic urine, ethanol or 2-propanol (isopropyl alcohol). Synthetic urine used in many of the tests described hereinafter is made from synthetic urine formulations made and commercially available from Jayco Pharmaceuticals (17055, Mechanicsburg, PA). Jicosynthetic urine prepared from the formulation is KCl 0.2%, Na ₂ SO ₄ 0.2%, NH ₄ H ₂ PO ₄ 0.085%, (NH ₄ ) ₂ HPO ₄ 0.015%, CaCl ₂ 2H ₂ O 0.025% and MgCl ₂ 6H ₂ O 0.05% (% by weight). Synthetic urine samples are prepared according to label instructions using distilled water. To aid dissolution, the Jacob salt mixture is slowly added to the water. The sample is filtered if necessary to remove all particles. Unused synthetic urine should be discarded after a week. In order to improve the visibility of the fluid, five drops of blue food coloring may be added per liter of the synthetic urine solution. The used jersey synthetic urine has a surface tension of 65 ± 5 dynes / cm.

2) free absorption capacity

The free absorbing capacity can be quantified for the present invention by measuring the amount of synthetic urine absorbed by the absorbed substance sample saturated with synthetic urine.

The sample and J. Synthetic urine were equilibrated to a temperature of 88 ° F. (31.1 ° C.). Measure at ambient temperature.

The crushed sample sheet is immersed in a Jacobi urine bath to inflate and saturate to the free absorbing capacity. After 3 minutes, the saturated, expanded sheet is cut into cylinders with a circular surface area of 1 in ² (6.5 cm ² ) using a sharp circular die. The cylindrical sample is soaked in synthetic urine for an additional 3 minutes at 88 ° F. The sample was then removed from the synthetic urine solution and placed on a digital balance. Weighing pans with an area larger than the sample area and suitable balances with a resolution of less than 1 mg may be used. Examples of such scales include Mettler PM 480 and Mettler PC 440 (Mettler Instrument Corp .; Mettler Instrument Corp .; Highstown, NJ).

After measuring the weight (Ww) of the wet sample, the wet sample is placed between two fine plastic mesh screens on top of four disposable paper towels. The sample is pressed three times by rolling firmly on a top screen with a plastic rolling mill. The sample is then removed, soaked in distilled water for about 2 minutes and then pressed between mesh screens as above. Next, place between 8 layers of disposable paper towels (4 on each side) and apply 20,000 lbs of pressure with a Carver Laboratory Press. The sample was then removed from the paper towel and dried in a Fisher convection oven at 180 ° F. for 20 minutes before recording its dry weight (Wd).

The free absorbing capacity is a value obtained by subtracting the dry weight (Dw) from the wet weight (Ww) and then dividing by the dry weight (Wd) ((Ww-Wd) / Wd).

The measurement to determine the free absorbent capacity of the sample can be made simultaneously with the measurement to determine the resistance to compression deflection and / or the expansion factor.

3) Specific surface area per foam volume

The specific surface area per foam volume value is derived from (a) capillary suction specific surface area measured during infiltration of the dry foam structure, and (b) the density of the expanded foam structure after infiltration to saturation, rather than a direct measurement of the dried and broken foam structure. do. Referring to co-pending U.S. Pat.No. 07 / 989,270, filed December 11, 1992, by Dyer et al., The specific surface area per foam volume is described in detail, which is incorporated herein by reference.

4) capillary absorption pressure

The vertical absorption absorption capacity described in the co-pending test method section of US Pat. No. 07 / 989,270 filed December 11, 1992, filed by Dier et al., Incorporated herein by reference except that 31 ° C is used instead of 37 ° C. To generate capillary absorption isotherms. The curve is a plot of the absorbent capacity of each compartment as a function of absorbed height. The capillary absorption pressure is regarded as the height of the foam having an absorption capacity of 1/2 of the foam free absorption capacity.

5) Cantilever bend value

For fabric stiffness, the cantilever bend value of the present invention is measured using ASTM Method D 1388 (Selective A-Cantilever Test). This test should be modified as follows:

1) The sample is tested at 88 ° F and 55% RH.

2) The test sample contains the absorbent part rather than the fabric.

3) The flexural stiffness is measured only in the longitudinal direction because the longitudinal direction is the bending direction that causes the loss of fixation.

4) When the diaper is folded, the outer surface 64 is in the bending direction so that all the samples are bent toward the outer surface 64 and tested.

5) All samples are tested in both dry and saturated conditions.

6) The cantilever bend value is equal to the protrusion length as defined in ASTM Method D 1388.

6) retention of rigidity against periodic bending

Stiffness retention against bending is measured from data generated using cantilever bending values as described above, specifically,

a) Initial cantilever bending value of the test sample is measured as described above.

b) Then, the test sample is oriented so that the long ends are aligned and bent at an angle of 70 degrees for the vertical alignment in the first direction, again to 0 angle for the vertical alignment, and 70 degrees in the opposite direction to the vertical direction. Bend periodically at an angle. One bending cycle is defined as one bend at 70 degrees in each direction and then restored at 0 degrees.

c) The bending cycle is repeated 10 times at a rate of 10 bending cycles per minute.

d) The cantilever bending value for the bent sample is measured as described above.

e) The rigid retention ratio for the sample can be calculated by dividing the cantilever bending value measured after the sample is periodically bent by the initial cantilever bending value measured before the bend.

7) Wet Caliper and Dry Caliper

Caliper or thickness measurements for the present invention are made when the sample is under a limit pressure of 0.05 psi (350 Pa).

Samples for caliper measurements are provided. The sample is punctured into a cylinder having a 1 in ² (6.5 cm ² ) circular surface area using a sharp circular die. Place the double gauge on the sample as appropriate for the caliper measurement. Suitable gauges can be used with foot doors having a circular surface area of at least 1 in ² (6,5 cm ² ) and capable of measuring caliper dimensions up to 0.001 in (0.025 mm). Examples of such gauges include Ames Model 482 (Arms Corporation; Ames Co., Waltham, Mass.) Or Ono-Sokki Model EG-225 (Ono-Sokki Co., Ltd., Japan) There is. Caliper measurements of three separate samples were taken.

Each sample was then saturated using free synthetic urine to the free absorbing dose. After 2 minutes the caliper of each saturated fully inflated sample is measured again.

8) resistance to compression deflection

The resistance to compression deflection for the present invention can be quantified by measuring the amount of stress (% caliper reduction) produced in a fully expanded sample saturated with synthetic urine after applying a stress in the form of a 0.74 psi (5.1 kPa) limit pressure. . In essence, the difference between a caliper measured under a lower limit pressure (0.05 psi (350 Pa)) and a caliper measured at 0.74 psi (5.1 kPa) defines the stress generated by the higher limit pressure. This method is more fully described in the Test Methods section of co-pending US patent application Ser. No. 07 / 989,270.

While specific embodiments of the invention have been described and described, it will be apparent to those skilled in the art that various other changes and modifications can be made without departing from the object and scope of the invention. Accordingly, all such changes and modifications are intended to be covered in the appended claims within the scope of the invention.

Claims (30)

Having a longitudinal centerline and a lateral centerline defining a longitudinal direction and a lateral direction, a longitudinal edge, a crotch region, a first waist region and a second waist region, respectively; Outer cover, An absorbent core connected to the outer cover and including one or more redistribution components capable of moving aqueous body fluid from the crotch region to one or more of the waist regions, Means disposed in the waist region to generate lateral tension through at least a portion of the waist region, and Located in at least one waist region and effectively in fluid communication with the absorbent core and having a caliper growth ratio of at least 3.0: 1, at least part of the loss of fixation due to reduced lateral tension in the waist region when the absorbent article is worn A supportive waist portion comprising at least one layer of absorbent foam capable of Absorbent product fixed around the wearer's body. The method of claim 1, Wherein said outer cover comprises a liquid impermeable topsheet coupled to a liquid impermeable backsheet and a backsheet, wherein an absorbent core is positioned between the topsheet and the backsheet. The method of claim 2, And wherein the supportive waist portion has a caliper increase ratio of at least 5.0: 1. The method of claim 2, And wherein said supportive waist portion has a caliper increase ratio of at least 7.0: 1. The method of claim 2, And the supportable waist portion is an extension of the redistribution component and comprises an absorbent polymeric foam. The method of claim 5, The absorbent article is an absorbent polymer foam, wherein the water-dispersible water-in-oil emulsion (HIPE) foam. The method of claim 2, And the supportive waist portion is located in both the first waist region and the second waist region. Having a longitudinal centerline and a lateral centerline defining a longitudinal direction and a lateral direction, a longitudinal edge, a crotch region, a first waist region and a second waist region, respectively; Outer cover, An absorbent core comprising one or more redistribution components capable of moving aqueous body fluid from said crotch region to said waist region and connected to an outer cover, Means disposed in the waist region to generate lateral tension through at least a portion of the waist region, and A supportive waist portion comprising at least one layer of absorbent foam located in at least one waist region and in effective fluid communication with the absorbent core and having a cantilever bending ratio of at least 1.0: 1; Absorbent product fixed around the wearer's body. The method of claim 8, And the outer cover comprises a liquid impermeable backsheet and a liquid permeable topsheet bonded to the backsheet, wherein an absorbent core is positioned between the topsheet and the backsheet. The method of claim 9, And wherein said supportive waist portion has a cantilever bending ratio of at least 1.1: 1. The method of claim 9, And said supportive waist portion has a cantilever bending ratio of at least 1.3: 1. Having a longitudinal centerline and a lateral centerline defining a longitudinal direction and a lateral direction, a longitudinal edge, a crotch region, a first waist region and a second waist region, respectively; Outer cover, An absorbent core comprising one or more redistribution components capable of moving aqueous body fluid from the crotch region to the waist region and connected to an outer cover, Means disposed in the waist region and generating lateral tension through at least a portion of the waist region, and A supportive waist portion located in at least one waist region and in effective fluid communication with the absorbent core and comprising at least one layer of absorbent foam having a rigid retention ratio of at least 0.9: 1 upon drying; Absorbent product fixed around the wearer's body. The method of claim 12, And the outer cover comprises a liquid impermeable backsheet and a liquid permeable topsheet bonded to the backsheet, wherein an absorbent core is positioned between the topsheet and the backsheet. The method of claim 13, And wherein said supportive waist portion also has a rigid retention ratio of at least 0.95: 1 when dry. Having a longitudinal centerline and a lateral centerline defining the longitudinal direction and the lateral direction, the crotch region, the first waist region and the second waist region, respectively; Liquid permeable topsheets; A liquid impermeable backsheet associated with the topsheet; An absorbent core positioned between the topsheet and the backsheet and including one or more fluid redistribution components; And a supportive waist portion located in the first waist region and in effective fluid communication with the absorbent core and including at least one layer of absorbent foam having a caliper increase ratio of at least 5.0: 1 and a cantilever bend ratio of at least 1.1: 1. A retention combination having a longitudinal side and a lateral end defining a perimeter; At least one pair of laterally extending side panels located at least partially in one or more waist regions, each of which is laterally outwardly connected to one of the longitudinal sides of the retaining combination; And A fastening system positioned in the first waist region and the second waist region and generating lateral tension through at least a portion of the waist region, Absorbent product fixed around the wearer's body. The method of claim 15, A pair of longitudinally extending side panels at both the waist shield, the first waist region and the second waist region located between the supportive waist portion and the topsheet; And a longitudinally extending elasticized leg cuff connected to the longitudinal side of the retaining combination. The method of claim 16, The side panel of the second waist region is elasticized, the fixation system comprises tape securing means and the elasticized leg cuff comprises two elongated cuffs. The method of claim 17, And wherein said supportive waist portion has a caliper increase ratio of at least 7.0: 1. The method of claim 16, The absorbent article further comprising an elasticized waist portion extending longitudinally inwardly from the lateral end of the retaining assembly in the second waist region toward the absorbent core and comprising at least a portion of the topsheet and the backsheet. . A longitudinal centerline and a lateral centerline defining the longitudinal and lateral directions, respectively, the longitudinal side and the lateral ends defining the perimeter of the absorbent article, the crotch region, the first waist region and the second waist region; Liquid permeable topsheet, Liquid impermeable backsheet connected to the topsheet, An absorbent core positioned between the topsheet and the backsheet and comprising one or more fluid redistribution components, A fastening system positioned in the first waist region and the second waist region to generate lateral tension through at least some of the waist regions, and A supportive waist portion located in at least one waist region and in effective fluid communication with the absorbent core and including at least one layer of absorbent foam having a caliper increase ratio of at least 5.0: 1 and a cantilever bend ratio of at least 1.1: 1; Absorbent product fixed around the wearer's body. The method of claim 20, And the supportable waist portion is an extension of the fluid redistribution component and comprises HIPE foam. The method of claim 20, A side panel extending laterally in the first waist region and the second waist region, a waist shield positioned between the supportive waist portion and the topsheet and a longitudinally extending elasticization connected to the longitudinal side of the absorbent article at least in the crotch region; An absorbent product further comprising a broken leg cuff. The method of claim 22, An absorbent article in which the side panels in the second waist region are elasticized. The method of claim 22, Absorbent article comprising tape securing means. The method of claim 22, Absorbent article wherein the securing system comprises a mechanical securing means. The method of claim 22, And the elasticized leg cuff comprises two elongated cuffs. A longitudinal centerline and a lateral centerline defining the longitudinal and lateral directions, respectively, the longitudinal side and the lateral side defining the periphery of the absorbent pants, the crotch region, and a first longitudinal edge and a second longitudinal edge, respectively; Having a first waist region and a second waist region; Outer cover, An absorbent core comprising one or more fluid redistribution components capable of redistributing aqueous body fluid from the crotch region to the waist region and connected to the outer cover, A supportive waist portion positioned in at least one waist region and in effective fluid communication with the absorbent core and comprising at least one layer of absorbent foam having a caliper increase ratio of at least 5.0: 1 and a cantilever bend ratio of at least 1.1: 1, Means for generating a lateral tension through at least a portion of the waist region and located in the first waist region and the second waist region, and A seam connecting the first longitudinal edge of the first waist region with the first longitudinal edge of the second waist region and connecting the second longitudinal edge of the first waist region with the second longitudinal edge of the second waist region; Absorption pants containing seam). The method of claim 27, The outer cover comprises a liquid impermeable backsheet and a liquid permeable topsheet bonded to the backsheet, an absorbent core positioned between the topsheet and the backsheet, the absorbent core further comprising a capture component . The method of claim 28, The absorbent pant further comprising a longitudinally extending elasticized leg cuff connected at least in the crotch region to the longitudinal side of the absorbent pant, wherein the means for generating lateral tension comprises an elasticized side panel. The method of claim 27, And the supportive waist portion extending longitudinally into the first waist region and the second waist region.

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